Part Number: PROCESSOR-SDK-AM335X
Other Parts Discussed in Thread: AM3352
Tool/software: Linux
Hi,
I am using am3352 with SDK 5.0.0.15. Two chips are connected to I2c. ADC 0x4C is accessible and EEPROM 0x51 is not.
My dts is as following:
i2c0: i2c@44e0b000 {
compatible = "ti,omap4-i2c";
#address-cells = <1>;
#size-cells = <0>;
ti,hwmods = "i2c1";
reg = <0x44e0b000 0x1000>;
interrupts = <70>;
status = "disabled";
};
i2c0_pins: pinmux_i2c0_pins {
pinctrl-single,pins = <
AM33XX_IOPAD(0x988, PIN_INPUT_PULLUP | MUX_MODE0)
AM33XX_IOPAD(0x98c, PIN_INPUT_PULLUP | MUX_MODE0)
>;
};
&i2c0 {
pinctrl-names = "default";
pinctrl-0 = <&i2c0_pins>;
status = "okay";
clock-frequency = <400000>;
U14_adc: U14_adc@4C {
reg = <0x4C>;
};
/*system eeprom*/
U21_24c512: U21_24c512@51 {
reg = <0x51>;
};
};
When I did:
>devmem2 0x44e0b000 (The control register of i2c0)
/dev/mem opened.[ 760.481821] Unhandled fault: external abort on non-linefetch (0x1018) at 0xb6f1b000
[ 760.490741] pgd = c1e5c000
[ 760.493460] [b6f1b000] *pgd=81d12831, *pte=44e0b303, *ppte=44e0ba33
Memory mapped at address 0xb6f1b000.
Bus error (core dumped)
I tried i2c tools
root@am335x-evm:~# i2cdetect -r 0
WARNING! This program can confuse your I2C bus, cause data loss and worse!
I will probe file /dev/i2c-0 using read byte commands.
I will probe address range 0x03-0x77.
Continue? [Y/n] y
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- 4c -- -- --
50: -- UU -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --
root@am335x-evm:~# i2cset 0 0x51 0xf 0xf
Error: Could not set address to 0x51: Device or resource busy
root@am335x-evm:~# i2cset 0 0x4c 0xf 0xf
WARNING! This program can confuse your I2C bus, cause data loss and worse!
I will write to device file /dev/i2c-0, chip address 0x4c, data address
0x0f, data 0x0f, mode byte.
Continue? [Y/n] y
root@am335x-evm:~# cd /sys/bus/i2c/devices/
0-0050/ 0-0051/ i2c-0/
root@am335x-evm:~# cd /sys/bus/i2c/devices/i2c-0/
0-0050/ 0-0051/ device/ i2c-dev/ of_node/ power/ subsystem/
I also tried
open(/dev/i2c-0,O_RWDR)
open is successful, but when read/write(fd, data, count) got I2C Error.
Can anybody help me to find the problem?
